NHK: Latest from Reactor No. 3 “may pose a problem” for efforts to remove melted fuel at bottom — No sign of water leakage from suppression chamber (VIDEO)

Published: July 13th, 2012 at 2:36 pm ET
By
Email Article Email Article
16 comments


Robot probe detects high radiation at No.3 reactor
NHK
Jul. 13, 2012

[Tepco] has detected high levels of radiation in the basement of the No. 3 reactor, with a maximum dose of 360 millisieverts per hour.

[Tepco] sent in a robot on Wednesday to the room where the suppression chamber is located. It was the first robot to probe this area of the plant.

[...]

They show that a door on the southwestern side is broken. There is no other apparent damage or sign of water leakage.

But high levels of radiation were detected. Readings exceeded 100 millisieverts per hour in a number of locations. Average levels were higher than those in the No.2 reactor.

Lost Robot

Engineers lost control of the remote-controlled robot after around 3 hours of operation. They say there are problems with the connecting cable and they’ve been unable to regain control.

TEPCO officials say they have no option but to leave the robot where it is for the time being.

This may pose a problem to the utility’s efforts to decommission the reactor. The operators are in a hurry to identify and repair damage to the reactor’s suppression chamber and containment vessel. They want to pump in water in order to remove the melted fuel lying at the bottom.

h/t Anonymous tip

Published: July 13th, 2012 at 2:36 pm ET
By
Email Article Email Article
16 comments

Related Posts

  1. NHK: Suppression chamber “may have been destroyed” at Reactor No. 2 (VIDEO) March 28, 2012
  2. Water level now below BOTTOM of fuel rods in No. 1 — Suggests nuclear fuel is in a molten mass at bottom of reactor (VIDEO) May 12, 2011
  3. NHK: Tepco can’t find holes at Reactor No. 2 — Nuclear Expert: It’s leaking like a sieve — “No one knows how they’re ever going to remove fuel in my lifetime” — Likely 50, 60, 70 years — Radiation like outer space (VIDEO) April 18, 2012
  4. NHK: Holes near bottom of containment vessel identified for first time at Fukushima plant — “Gushing out” of Reactor No. 1 — Similar damage suspected at Units 2 and 3 (VIDEO) November 13, 2013
  5. Gundersen’s Latest: 60 holes in bottom of Fukushima-type reactors make core melt-through easier — Fuel only had to get through a thin pipe, not inches of steel (VIDEO) September 20, 2011

16 comments to NHK: Latest from Reactor No. 3 “may pose a problem” for efforts to remove melted fuel at bottom — No sign of water leakage from suppression chamber (VIDEO)

  • markww markww

    There seems to be a fire in unit 3 reactor which has been burning now for three hours I first saw it around 9:36 AM today's date 7-13-2012 Central Time It is still there if you look

    Look at the tallest white release tower and at the bottom right you see a small crane at unit three there is a red glow there and saw the red glow as a spot on the JNN camera but if you look on the Tepco cam you can see the red glow through and left of the crane I do not know if we have a Radioactive core fire or not but the red glow is not goodMark


    Report comment

  • Max1 Max1

    From the article:

    "This may pose a problem to the utility’s efforts to decommission the reactor. The operators are in a hurry to identify and repair damage to the reactor’s suppression chamber and containment vessel. They want to pump in water in order to remove the melted fuel lying at the bottom."

    I was under the impression that there was water already being pumped in… you know, cooling the reactor in "COLD SHUTDOWN".

    The spin…


    Report comment

  • PhilipUpNorth philipupnorth

    There is a lot in this cryptic paragraph. What does it tell us?
    "This may pose a problem to the utility’s efforts to decommission the reactor. The operators are in a hurry to identify and repair damage to the reactor’s suppression chamber and containment vessel. They want to pump in water in order to remove the melted fuel lying at the bottom."
    The failure of the robot may delay efforts to decommission Unit3. Said this before: There is no point even looking at this floor. This floor sits on TOP of the Torus. Any holes will be through the BOTTOM of Torus3, or through the BOTTOM of Containment3. Fools errand, and lost the robot. After a year and four months!

    "Identify and repair" holes in the bottom of Torus and Comtainment may be difficult. If they pump water out of the lower floor of the Torus room, the radiation level will go way up. No human welder will be able to make repairs here in any case, because there will be lots of corium where the holes are. Better to pop the tops on those Torus hatches, and fill the Torus with some of that concrete that sets underwater.

    "Pump water in" is something that makes no sense at all. If you patch the hole in the bottom of Containment3, the patch will cover any remaining corium. So there will be no "melted fuel" to recover. Can they get to the bottom of Containment3 to patch it? Probably not.

    They are having trouble even LOOKING at Unit3. "In a hurry?" TEPCO'S TOTAL LACK OF EFFORT is what is…


    Report comment

  • PhilipUpNorth philipupnorth

    TEPCO's own lack of effort is what is holding things up. X 3 reactor melt-throughs, and X 7 SFPs.


    Report comment

    • Max1 Max1

      Yep!
      Just think… ONE SFP in 16-18 months X 7 equals HOW MANY YEARS?
      And THAT's just to begin emptying the SFP's… God forbid any further TEPCO-blunders.

      And this proves that nuclear is safe, people…
      /snark.


      Report comment

  • gottagetoffthegrid

    "They want to pump in water in order to remove the melted fuel lying at the bottom"

    they ARE pumping water into the contaiment. the 9 m^3 per hour that is being pumped into the RPV is flowing out the hole in the bottom of the RPV where the core melted through.

    the core is nowhere near the bottom of the PCV; it has left the building.


    Report comment

  • wearealldoomed

    seems to me theres a lot of demo to do before they can even think about removing any of the spent fuel in #3, lets hope they get enough practice removing #4's fuel first…..SHLEPCO is unbelievable….what a bunch of F'ing jokers!!!


    Report comment

  • weeman

    May pose a problem, what revaluation made you think that, was it the condition of the structure, because you lost your robot, poor thing you care more for robot than people, was it the high radiation levels in basement, is it that you have not a clue how to remedy the situation, have you come to realize that you should not have been playing with something you do not fully understand, control or fix, all in the name of cheap power that is the most expensive to produce if you factor in disposal and decommissioning, a fact they do not take into the equation of cost, you have conformation of the china syndrome and know it will never be under control, do you have conformation that the SFP was on fire.
    I hate silly answers and questions, we know that, just take a look.


    Report comment

  • razzz razzz

    These reports are so poorly written or maybe it's something lost in translation. Whatever it is, the reports are not forthcoming with useful information other than the radiation readings are high and we lost our robot so how do you expect us to know what we are doing when we can't handle the simplest matters.

    I take it, they want a closed loop so to control the coolant/water flow and level at all times during any attempts at melted fuel removal. Doesn't even have to be a pressurized loop just a loop that doesn't leak and can maintain a certain water level.

    If the corium flow starts with any remaining fuel in the reactor vessel and runs ending on the containment base-mat then they need to be able to flood above the highest area of fuel if they want to remove the lid(s) to work underwater chipping away at the radioactive lava. Without airtight containment, working underwater is about the only way to control radioactive particle releases besides to keep the remnants cool.

    So, they are trying to find the leaking areas or points then figure out how to seal them up. Holes they can be plugged, cracks they can be injected, damaged pipes they can be capped.

    I still think all (3) reactor melted cores are sitting on base-mat concrete in various forms leading back to the bottom of the reactors, a good thing as far as keeping the coriums in place. Coolant waters leaking into the ground and out to sea besides the any steaming to atmosphere is better than the coriums…


    Report comment

    • Radio VicFromOregon

      razzz, i agree, these engineers are working this as best as the available technology allows, which isn't enough, but will have to do. I truly hope that people here are making a distinction between TEPCO elites and their desire to cover up and the nuclear engineers and their desire to end this disaster.


      Report comment

  • chrisk9

    What the heck are they talking about!!
    "This may pose a problem to the utility’s efforts to decommission the reactor. The operators are in a hurry to identify and repair damage to the reactor’s suppression chamber and containment vessel. They want to pump in water in order to remove the melted fuel lying at the bottom."
    Pure 100% fantasy. Repair damage to the suppression chamber and containment vessel-will never happen. Remove melted fuel-will never happen. I am starting to believe they they really believe these things. The dose rates from the loose fuel throughout all these units (it's everywhere in the plant) will prevent this from happening for 300+ years. (10 half lives of cesium).
    Think about the other thread that discusses decontaminating a school, and after they leave it's come back just as contaminated. That's a million times easier than decontaminating or removing melted fuel. These people are complete wack jobs who obviously are not listening to any outside experts, because anyone with much nuclear experience will tell you they have lost their minds.


    Report comment

  • "They want to pump in water in order to remove the melted fuel lying at the bottom."… "I am starting to believe they they really believe these things."

    Sure they believe it. Arnie Gundersen told them the fuel is in a cold pancake at the bottom of the containment. Everybody loves Arnie.


    Report comment